title: Quantitative and qualitative assessment of bone perfusion and arterial contributions in a patellar fracture model using gadolinium-enhanced magnetic resonance imaging: a cadaveric study.
abstract: BACKGROUND
  The purpose of the present study was to evaluate the anatomy and contribution of the patellar vascular supply and to quantify the effect of a transverse fracture on patellar perfusion.
  
  
  METHODS
  In twenty matched pairs of fresh-frozen cadaveric knees, the superficial femoral artery, anterior tibialis artery, and posterior tibialis artery were cannulated. One side of each matched pair was randomly selected to undergo one of two osteotomies: (1) midpatellar osteotomy or (2) distal-pole osteotomy. For volumetric analysis, comparisons were performed between contrast-enhanced magnetic resonance images and precontrast magnetic resonance images as well as between osteotomized patellar bone fragments and the corresponding intact areas on the control side. We then injected a urethane polymer compound and dissected all specimens to examine extraosseous vascularity.
  
  
  RESULTS
  Magnetic resonance imaging demonstrated that the largest arterial contribution to the patella entered at the inferior pole in 100% of the specimens; in 80% of these specimens, the artery entered inferomedially. It also revealed an overall decrease in contrast enhancement in both transverse osteotomy groups, with an average reduction in enhancement in the proximal fragment of 36%.
  
  
  CONCLUSIONS
  If possible, surgical interventions about the knee should be carefully planned to preserve the peripatellar ring (the source of the entire patellar blood supply), especially the inferior patellar network. Distal-pole patellectomy should be avoided to retain vascularized bone at the reduced fracture site.
authors.affiliation: Orthopedic Trauma Service, Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021. E-mail address for L.E. Lazaro: lionellazaro@gmail.com.
authors.forename: Lionel E
authors.initials: LE
authors.lastname: Lazaro
authors.forename: David S
authors.initials: DS
authors.lastname: Wellman
authors.forename: Craig E
authors.initials: CE
authors.lastname: Klinger
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Dyke
authors.forename: Nadine C
authors.initials: NC
authors.lastname: Pardee
authors.forename: Peter K
authors.initials: PK
authors.lastname: Sculco
authors.forename: Marschall B
authors.initials: MB
authors.lastname: Berkes
authors.forename: David L
authors.initials: DL
authors.lastname: Helfet
authors.forename: Dean G
authors.initials: DG
authors.lastname: Lorich
mesh_terms: D002102:Cadaver; D002404:Catheterization; D003287:Contrast Media; D004210:Dissection / Q000379:methods; D005260:Female; D005263:Femoral Artery / Q000033:anatomy & histology; D050723:Fractures, Bone / Q000473:pathology*; D019786:Gadolinium DTPA; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D010027:Osteotomy / Q000379:methods; D010329:Patella / Q000098:blood supply* / Q000293:injuries / Q000601:surgery; D016909:Tibial Arteries / Q000033:anatomy & histology
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA